Reflector



J. O. HELLIWELL REFLECTOR Filed June 13 1921 acitizen' of the United States, residing at ,To all whom a may am..-

PATENT 1,517,362 OF ICE 301m 0. muwnnn, or rasnmina, cnmronmn.

, .nnrnnc'ron. I i

. limitation menus 18,1921. as... 477,101

' Be it known that I, JOHN O. Hnni.1wniin,

Pasadena, county of Los Angeles, State of California, have inventednew anduseful Improvements in J Reflectors; and I do herei by declare the following-to 'bea full, clear,

f and exact description of ,the invention, such flector.

The object of this inventionis; to provide a reflector which shall-render-theheadlamp to which it is applied so free fromobjection able glare as to make'it complywith the vari- It is a'further provide a reflector" of suchconformation v'ous State traflic lawsand obviate thenecessity of lenses or dimmers.

Itisa further object of this invention .to provide a reflector of such conformation that .a maximumnumber of light rays shall be projected on the planeof travel and without,

sacrificing the distance at which 3 the head light functions. object of this invention to I that the .maximum, amount ;-of lighting energy be projected rather than be reflected in an upward direc: tion a'ndlost. c.

It is a further object of this invention to provide avreflector of such conformation that the light rays from thevupper part of the reflector shall cross those reflected from the lower part so as to effect a partial diffusion of the light.

It is a further object of thisinvention to provide a reflector which may be adapted to the standard headlamp casing and which will permit of the inclination rays to eliminate objectionable adjusted by adjusting the light than by't ilting the headlamp. j

With these and other objects'in view, the invention consists in the unique conformaglare being 'ulb rather tion and construction referred to as a conoidal reflector hereinafter described, illustrated inv the accompanying drawing and pointed out in the claims hereto appended;

it being understood that variouschanges 1n the form, proportion, conformation, size and minor details of construction, within the proper scope of the claims,'may be resorted to without defiiirting from the spirit or sacri ficing any of e advantages of the invention.

vPosition of foci- "Like letters of reference .respondmg parts in the several figures ofsurface.

along the path of travelof; the light It also to be understood that while in the .the basic principle of-this application. p

Inthe drawing:

j 1- Figure lis a verticalsection'of" Fig. .3

as will enable others skilledinthe artto which it appertains to; make and use the 's m c This invention, relates tea 'conoidal re showing the .generalshape and conformadirection of the reflected light rays, but with light bulb omitted.

{Fig.2 is the top view of the reflector.

Fig. 3 is a front elevation. a

' Fig.4 is a side elevation. i

designate corthedrawing. j j This reflector, a preferredembodiment of which is illustrated in the accompanying drawing, comprises aconcave body of suitable material, and'so treated on its inner surface/as to afford a suitable reflecting ,--The introduction of a light bulb connection is provided for by the opening (BC) This reflector is designed to perform the usual functions of a reflector as well as ach eve the objects above mentioned.

These objects are attained becauseof the factthat the inner surface of this conoidal reflector is the composite of aninfinite number of conicfsections of varying focal lengths. Hereinafter. parabolic: conic sections will be .referred to,- bothin the 3 specifications and drawing,but as stated above, this is merely byway of concrete example.

' For example in the illustration accompanyingthese specifications (Fig. 1) the foci of the parabolas fall between (-Y), which is thefocal point of (A-B) and (X), which is the focal point of (G-D). While in Fig. 1 ,of the drawing the parabolas,

-(A B) "and (G-D are respectively the upper and lower parabolas it is only necessary that they be substantially so to give the desired result.

Because of the fact that-if the source of light of a parabolic reflector be a point placed at'the focal point the resultant reflectedbeam will be projected parallel to the axis of the parabola-if the source of light be placed at (Y) the resultant beam will be 11 htray (R) parallel to (H-PH);

On the 0 er hand, should the source of light in I order v to show the tionof the surface. s

Because of. the fact. that practicethe.-

be placed at point (X) the resultant'beam (T) reflected from (C-D) will be parallel to (lH-H). Furthermore, when the source of ight is placed in this position at (X) the resultant beam (S) reflected from A-- B) will converge towards (HH). his last osition of the source of light at, (X) is su b rays from the greater art of'the surface of such reflector and en stantiallyhorizontal beams from the lowest and remaining por source of light is not a oint'as in theo may be deemedadvisableto place" the bulb filament slightlyto the 'rear of (X) .so-that the secondary rays from the outerperiphery .'of the bulbfilament willreflected from C"- D) in a horizontal" direction. Therelative position of the light bulb between (XY) will control the downwardinclination been the reflectedrays,"thus affording an easy method of regulating'the angle of projection onto the surface of theroad.

I the drawing While it is to be noted that in Fig. '1 or olas approximately coincidej so longv as their apexes fall substantially betw e jm);

? With a reflector as described 'tandillusv trated and with proper adjustment 10f" the light bulbfilament no light rays will 1 be and (G).

projected u wardly from-its surface.

WhatIcaimis: 1. A conoidal reflector theinnersurface of which isthe composite of an infinite nummaximum focal lengths, said conic sections f havmga common apex. I

stantially the one to obtain the 'desired results, giving downwardly reflected 4. Aconoidal reflector the inner surface' 0f which is the composite of an infinite num f her of conic sections having all the parabolas 'havea comn monaxis coinciding with (H- H) it is only: necessary that the several axes of the parab- 2. A conoidal 1 reflector the innersurface of which is the compositecf, an infinite number of conic sections having;a multiplicity of foci having a general axial disposition and of which the substantially uppermost,

conic section is shortest in focal length and such minimum and maximum focal len hs.

'3. A conoidal reflector, being substantially vcircular in vertical. transverse. section, the inner'surface of whichis' the composite of an infinite'number of conic sections havin ia'n lulti lic'ityof foci witha general axi but an area the size of t e bulbjfilament 1t i 'dispositiomof which the substantially upw permost conic section is shortest in focal longest in focal length and all the other conic sections in focal length fall. in between such minimum" and maximum focal of foci with a ge'neral'axia tion isvshortestin focal length and the substantiall lowermost conlc section is longest in focal ength and of which all other conic sections are of such intermediate focal "length that thelatera'l distribution of light shall be greater" than the tion in area.

vertical distribua multiplicity disposition, of I which the substantially uppermost conic sec- 15. A conoidal reflector being substantially v circular in'vertical transverse section. and

having a common axis,'the inner surface of s which is the composite of'an infinite numa multiplicity of foci with a general axia disposition, of

ber of conic sections havin which the substantially uppermost conic.sec-' tionis shortest in focal length and the substantially lowermost conic section is longest in focal length and all the other conic sections in focal length fall in between such minimum and maximum focal lengths.

JOHN, o. mLLrwE L. 

